Effect of Zinc Fertilizer Rates on Grain and Straw Zn Content, and Grain Yield of Chickpea Varieties in Southern Ethiopia

Abstract

አህፅሮት

 የዚንክ ንጥረ-ይዘት ለሚያጥርባቸው የእርሻ መሬት የዚንክ ማዳበሪያ መጨመር በምርትም ሆነ በምርት የዚንክ ንጥረ-ይዘት ላይ አወንታዊ እመርታ እንደሚያሰገኝ ይታመናል፡፡ ሆኖም የሚጨመረውን የማዳበሪያ መጠን የሚወስነዉ የአፈር ውስጥ የዚንክ ንጥረ ይዘት እጥረት መጠን፣ የአፈሩ ዓይነት፣ የስብል ዓይነትና ዝርያ እንዲሁም የአጨማመር ዘዴ ነዉ፡፡ የዚህ ጥናት ዓላማ የሽምብራን ምርትና የምርት ዚንክ ንጥረ-ይዘት መጠንን የሚያሻሽል የዚንክ ማዳበሪያ መጠንን ለዚንክ ንጥረ-ይዘት መጠን አነስተኛ ለሆነ መሬት ለመወሰን ነው፡፡ የአፈር ዚንክ መጠን ዝቅተኛ ከሆነበት የእርሻ መሬት እና ከዚሁ ማሳ በተሰበሰበ አፈር ላይ ሶስት የሽምብራ ዝርያዎች በሰባት የዚንክ ማዳበሪያ መጠን  በ2004 እና በ2005 የምርት ዘመን ተጠንቷል፡፡ በማሳ ላይ የተደረገው ጥናት ውጤት የሚያመለክተው ሁለተኛ ጮሮቆ ከጣባም ሆነ ከጆሌ አንደኛ አካባቢዎች በ46.67 በመቶ የተሸለ የምርት ዚንክ ንጥረ-ይዘት የተገኘበት ሲሆን  በልዩ መደብም ሆነ በማሳ ላይ  የተደረገው ጥናት ውጤት የሚያመለክተው ከዝርያዎቹ ማስተዋል የተባለ የሽምብራ ዝርያ ከሌሎቹ የተሸለ ምርት ሲገኝበት፣ ሀብሩ ደግሞ በገለባ የዚንክ ንጥረ-ይዘት ተሸሎ ተገኝቷል፡፡ የአካባቢው ዝርያ በምርት የዚንክ ንጥረ-ይዘት ከፍተኛ ሲሆን የዝርያና የማዳበሪያ ዉህደት በሽምብራ ምርትና በምርት ንጥረ-ይዘት ላይ እመርታዊ ጭማሪ ያስገኘ ሲሆን 25 ኪሎ ግራም ዚንክ ማዳበሪያ በሄክታር በሁሉም ዝርያዎች ከፍተኛ መሆኑን ያሳያል፡፡ ከዚህ በላይ የማዳበሪያ መጠኑን መጨመር የተለየ ዉጤት አላሳየም፡፡ ስለዚህ ይህ ጥናት የሚያረጋግጠው ሽምብራን በዚንክ ንጥረ-ይዘት ለማበልፀግ ዝርያና ማዳበሪያ አጠቃቀምን በመመጠን እንደሚቻል ነዉ፡፡

Abstract

 Application of Zn had a significantly positive effect on grain Zn concentrations and also on grain yield especially under Zn deficient conditions. The amount of Zn required to alleviate Zn deficiency varied with severity of deficiency, soil types, nature of crops and cultivars. The response of chickpea varieties to Zn nutrition was studied in pots and on fields using zinc deficient soils during 2012 and 2013 cropping seasons to determine zinc fertilizer rate which improve zinc content and productivity of the crop. A factorial combination of three chickpea varieties and seven zinc fertilizer rates were laid in Randomized Complete Block design with three replications for both pot and field experiments. The result of pot experiment revealed that, variety Mastewal produced the highest grain yield (5.9 g pot^-1) and Habru produced highest (35.99mg kg^-1) straw zinc content. Conversely, local chickpea provided the highest (36.1mg kg^-1) grain Zn. Chickpea varieties and zinc fertilizer rates interaction on grain yield was significant where 25kg ha^-1 produced highest regardless of the varieties. Similarly, location had significant (p<0.01) effect of grain zinc content where Choroko produced 46.6 % more grain zinc content than both Taba and Jolle. Highest straw zinc (24.96 mg kg^-1) obtained from variety Habru, while highest grain zinc obtained from the application of 25 kg ZnSO₄ .7H₂O ha^-1 with either of the varieties which was at par with the highest Zinc rate (30kg ha^-1). Significant interaction effect of variety by location on grain yield and straw zinc content was observed. The variety Mastewal was superior in grain yield at Jolle and Choroko, while landrace performed better at Taba. The landrace and Habru were higher in straw zinc content across locations. Moreover, 25 kg ZnSO₄ .7H₂O ha^-1 resulted in 7 and 8% more grain and straw zinc content over the control, in that order. Thus, the current research inveterate a possibility of agronomic intervention for zinc fortification of chickpea through zinc fertilizer management.